This year, we have investigated following five subjects ; 1. studies on advanced pretreatment of coal (Profs.Moro-oka and Cheng), 2. deep desulfurization of coal derived liquids (Profs.Kabe and Sha), 3. studies on extractive liquefaction (Profs.Iino and Guo), 4. studies on development of new method for coke production (Profs.Nomura, Guo, and Dr.Du), and 5. studies on development of catalysts for production of chemicals from CO and CO_2 (Profs.Inui and Zhu).As to subject No.1, we have carried out following experiments ; Methyl, ethyl, octyl, naphthylmentyl or tetralylmethyl groups were introduced to a brown coal by O-alkylation. Then the alkylated coal was pyrolyzed in a fixed-bed reactor. The most significant increase in the tar yield was observed with octylated coal. Then, some low-rank coals were impregnated and coated with some long paraffinic alcohol or polyolefins (polyethylene and polypropylene) by heating at around 200 ^ﾟC. The resulting coals were pyrolyzed in an entrained-flow
… More reactor. Both alcohol increased effectively the yield of volatile matters and liquid products.As to subject No.2, in order to estimate the mobility of sulfur on the catalyst during desulfurization, hydrodesulfurization of ^<35>S-labeled dibenzothiophenewas investigated by using sulfided Ni-Mo/Al_2O_3 catalyst. It was clarified that the amount of labile sulfur changed greatly depending on reaction conditions. Further, it was suggested that sulfurs having a bonding manner of Ni-S-Mo would be labile.As to No.3, we found that for bituminous coals, the extraction yield with a mixed solvent of carbon disulfid-N-methyl-2-pyrrolidinone was increased by the heat treatment at 175-300 ^ﾟC in hydrogen donating solvent such as 9, 10-dihydroanthracene and 1, 4, 5, 8, 9, 10-hexahydroanthracene. On the other hand, the yield enhancement was found to be very small for a brown coal.As to subject No.4, in order to develop a new continuous method for coke production with energy saving, we have carried out following experiments ; Cokes were prepared by the rapid heating up to 340 ^ﾟC, compression at 250 ^ﾟC under 342 kgf/cm^2, followed by carbonization at 800 ^ﾟC for 2h. The tensile strength of the cokes prepared from Goonyella, Witbank, and Byron Creek coals were 45, 6, and 2 kgf/cm^2, respectively. The tensile strength of the cokes obtained from the latter two coals was increased by keeping volatile materials in it during the reaction and/or adding of coal tar pitch to it.As to subject No.5, application of metallosilicate catalysts to various coal conversion processes was examined. In the gasoline synthesis from syngas and CO_2-H_2 via methanol using serially connected reactors, H-Fe-silicate adopted for the second stage reactor predominantly afforded iso-mono-internal-olefins. Selective hydrogenation of these olefins to isoparaffin-rich gasoline was achieved by Pt-loaded non-metal-silicate. In upgrading of a coal liquid fraction, H-Ga-silicate has excellent performance for the formation of aromatics.This year, we have invited 10 researchers from China and discussed above subjects with them. Less